Robert dangar dixon



No. 622,332. Patented Apr. 4, I899 R. D. DIXON.

ANIMAL SHEARS.

(Application filed Jan. 7, 1899.)

2 Sheets-Sheet I.

(No Model.)

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No. 622,332. Patented Apr.'4, I899. R. D. DIXON.

ANIMAL SHEARS.

(Application filed Jan. 7, 1899.)

2 Sheets$'heet 2.

(No Model.)

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ANIMAL- SHEARS.

SPECIFICATION forming part of Letters Patent Nd. 622,332, dated April 4,1899'.

Application filed January 7,1899- Serial No. 701,488. (No model.)

To a whom it may concern.-

Be it known that LROBERT DANGAR DIXON, a subject of the Queen of GreatBritain and Ireland, and a resident of Sydney, in the county ofCumberland and Colony of New South Vales, have invented a certain newand useful Animal-Shears, of which the following is a specification.

Hitherto, owing to the way in which the combs and cutters of machinesheep-shears have been made and ground, the cut that they effect has notbeen a true cut, but has been merely a breaking of the fiber bypercussion. In order that the percussive action of the outter upon thefiber may be effective, it has been found necessary to drive themachines at a very high rate of speed, and this, together with theexcessive tension that is required to be applied to the cutter,necessitates a much higher degree of power to drive the machines thanshould be necessary were the cut a true cut.

This invention has been specially devised with a View to obtain a truecut of the fiber by causing the cutting edges of the cutter to workalong the cutting edges of the comb in the same way as the two cuttingedges of a pair of scissors or a pair of hand-shears work together.

In the accompanying drawings, Figure 1 is a plan of the sheep-shears,the cover being laid open. Fig. 2 is a longitudinal vertical section ofthe same, taken through the central longitudinal axis of the machine.Fig. 3 is an underneath plan of part of the main actuating-lever and thetension-spring. Fig.

at is a front elevation of the comb and cutter,

showing the tension-bar. Fig. 5 is a section through the comb, showingthe action.of the cutter with the comb. Fig. 6 shows several alternativemodes of making the cutter whereby the scissors cut may be effected.

A is the central axial pin, which also serves as a tension-screw.

B is the main actuatinglever, which is forked at its rear end to receivethe antifriction-roller c of the driving-disk O, which is caused torotate by any suitable means. Below the lever B is riveted thetension-spring D, the forward end of which is forked, as at (I, so as toallow of the passage of the axial pin A. The forked part (1 of thespring D is inserted into a step-socket e, which is bored to permit of.the passage of the pin A, the upper end of which is threaded to receivethe tension-nut F, which when it is screwed down tight will be retainedin that position through the instrumentality of a stop upon the springf, which will engage with one of the peripheral notches in the nut F ina manner well known and understood. The forward end of the lever B isshaped like a fork, with three prongs b 1) b the two outside prongs bbeing provided underneath with studs d 01 which engage withcorresponding recesses in the cutter G. It is by means of the studs (1'd that the re ciprocatory movement of the lever B is communicated to thecutter G. The cutter G is of the two-pronged type, as may be seen byreferring to Figs. 1, 4, and 6. Bearing down upon the cutter G is thetension-bar H, which is pivoted to the central prong b by the screw h.By means of this tension-bar H the. tension is evenly distributed uponthe two teeth of the cutter. ground perfectly fiat on its upper side,but it may be made curvilinear or flat saucer-shaped for reasons to behereinafter explained. The under side. of the cutter G is hollow-ground,as shown in Fig. 5 and by the figure x of Fig. 6. The curve has beenexaggerated in the drawings to render it more apparent. By grinding thecutter hollow the result will be that the points of its teeth will dropinto the spaces between the teeth of the comb, and the cutting edges ofthe cutter-teeth will grind against the cutting edges of the comb-teeth,thus producing a true cut or shear on anything that is placed between.The effect is precisely similar to the shearing effect produced by thetwo blades of a pair of scissors or shears while they are in process ofbeing closed together.

Instead of hollow-grinding the cutter, as shown at at, Fig. 6, a verysimilar effect may be produced by slightly raising the heel of thecutter upon studs M, Fig. 6, yy, or upon a thin strip of metal 2', Fig.6, z z, or the cutter may be fiat-ground and the comb hollow orsaucerground on its upper surface. Either of these methods would produce thesame efiect-viz., that of depressing the points of the teeth of thecutter into the spaces between the'teeth of the comb--resulting inashear- The comb J is preferably ing action between the cutting edges ofthe teeth of the cutter and the comb; but the shearing action would noteventuate if the teeth of the comb were made parallel to one another, asis generally the case. I have therefore found it necessary to constructthe teeth of the comb and of the cutter on lines radiating fromthe'center of the axial pin A. Vhen the cutter reciprocates to and fro,it will always be parallel with the comb, and the shear or cut willalways be the same no matter at what part of the comb the cut takesplace.

Owing to the dip of the points of the teeth of the cutter into thespaces between the teeth of the comb the traverse of the cutter wouldnecessarily be somewhat u ndulatory, which but for the special devicesemployed could not fail to materially afiect the eiiiciency of thetension. Referring-to Fig. 2, it will be seen that the spring D wouldhave a tendency to elevate the rear end of the lever B, and thereby todepress the forks b b b at the forward end of the same, and if thecutter were rigidly secured to the forks the tension could not be evenlydistributed over the cutter. This objection is obviated by thetension-bar II, which is articulated to the central fork b by the screwh, so as to be susceptible of movement only in a plane at right anglesto the plane of movement of thelever, and therefore, no matter what maybe the position of the lever B, the tension will always be evenlydistributed over the cutter.

It is obvious that the principle of the hollow-ground cutter may beapplied with equal facility to horse-clippers and other appliances of ananalogous type.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is 1. In combination,in animal-shears, a comb having teethand a cutter having teeth which dip between the teeth of the comb,substantially as described.

2. In combination in animal-shears, the comb having teeth, and a cutterhaving a concaved under side with its teeth dipping between the teeth ofthe comb, substantially as described.

3. In combination, the comb, a cutter and a pivoted lever carrying thesame, the said cutter and comb having their teeth radiating from thepivotal point of the lever and the teeth of the cutter dipping inbetween those of the comb, substantially as described.

4. In combination,the comb, the cutterhaving the teeth, a lever foroperatingthe cutter anda tension-bar pivoted to the central part of theforward edge of the lever to move in a plane at right angles to theplane of movement of the cutter-lever, the ends of the tension-barbearing upon the outer portions of the cutter, substantially asdescribed.

5. In combination, the comb, the cutter, the lever for operating itconnected thereto, the axial pin about which the lever turns, thetension-spring connected to the lever at its rear end and forked at itsfront end to embrace the-axial pin, the stepped socket c inclosing theforked end of the lever, and the tensionbar at the front of the leverbearing on the cutter, substantially as described.

In witness whereof I have hereunto set my hand in presence of twowitnesses.

, ROBT. DANGAR DIXON.

Witnesses:

MANFIELD NEWTON, J As. T. HUNTER.

